Quantitative Exposure Assessment of Various Chemical Substances in a Wafer Fabrication Industry Facility

Abstract

ObjectivesThis study was designed to evaluate exposure levels of various chemicals used in wafer fabrication product lines in the semiconductor industry where work-related leukemia has occurred.MethodsThe research focused on 9 representative wafer fabrication bays among a total of 25 bays in a semiconductor product line. We monitored the chemical substances categorized as human carcinogens with respect to leukemia as well as harmful chemicals used in the bays and substances with hematologic and reproductive toxicities to evaluate the overall health effect for semiconductor industry workers. With respect to monitoring, active and passive sampling techniques were introduced. Eight-hour long-term and 15-minute short-term sampling was conducted for the area as well as on personal samples.ResultsThe results of the measurements for each substance showed that benzene, toluene, xylene, n-butyl acetate, 2-methoxyethanol, 2-heptanone, ethylene glycol, sulfuric acid, and phosphoric acid were non-detectable (ND) in all samples. Arsine was either "ND" or it existed only in trace form in the bay air. The maximum exposure concentration of fluorides was approximately 0.17% of the Korea occupational exposure limits, with hydrofluoric acid at about 0.2%, hydrochloric acid 0.06%, nitric acid 0.05%, isopropyl alcohol 0.4%, and phosphine at about 2%. The maximum exposure concentration of propylene glycol monomethyl ether acetate (PGMEA) was 0.0870 ppm, representing only 0.1% or less than the American Industrial Hygiene Association recommended standard (100 ppm).ConclusionBenzene, a known human carcinogen for leukemia, and arsine, a hematologic toxin, were not detected in wafer fabrication sites in this study. Among reproductive toxic substances, n-butyl acetate was not detected, but fluorides and PGMEA existed in small amounts in the air. This investigation was focused on the air-borne chemical concentrations only in regular working conditions. Unconditional exposures during spills and/or maintenance tasks and by-product chemicals were not included. Supplementary studies might be required.

Assessment of Arsenic Exposure by Measurement of Urinary Speciated Inorganic Arsenic Metabolites in Workers in a Semiconductor Manufacturing Plant

“…Prior studies assessing arsenic exposure in the semiconductor industry focused mainly on ion implantation process workers, in whom the level is known to be negligible [14]. In this study, however, urinary inorganic arsenic metabolites in clean process and ion implantation PM engineers were higher than in the non-exposed group, after adjustment for smoking and seafood intake.…”

Exposure Reconstruction and Risk Analysis for Six Semiconductor Workers With Lymphohematopoietic Cancers

“… 21 Benzene has not been detected in other investigations, including in wafer-fabrication facilities. 13 , 22 Monitoring for benzene at the facilities by the authors did not identify detectable concentrations (limits of detection: 0.006 to 0.008 ppm for 8-hour TWA, and 0.01 to 0.09 ppm for task-based samples).…”

Exposure assessment of workers in printed electronics workplace

“…Since most of the printing operations were conducted under cleanroom conditions, the particle exposure was not significant. However, organic solvent exposure can be significant for some cleanroom operations (Edelman, 1990;Park et al, 2011), as the re-circulation of workplace air in the cleanroom can result in increased organic solvent concentrations (LaDou & Bailar, 2007). Cases of cleanroom workers being intoxicated by organic solvents have already been reported in the semi-conductor industry in Korea (Kim et al, 2011).…”